• Proceedings of the Korean Society of Precision Engineering Conference
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• 2013.05a
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• pp.559-560
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• 2013

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2009.10a
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• pp.183-184
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• 2009

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1992.04a
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• pp.262-267
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• 1992

본 논문에서는 국내 중소기업을 위한 기술지원의 일환으로 시범적으로 개발한 자동화 모델을 소개한다. 개발된 모델은 자동차에 사용되는 오일 펌프 드리이브용 기어를 대상부품으로한 FMC(Flexible Manufacturing Cell)로서 선삭과 치절( Hobbing)공정을 자동화 하는 2 Set의 FMC로 구성되어있다. FMC 개발을 위하여 대상부품 특성과 공정을 분석하였으며 개발된 시스템의 구성 및 개별장비에 대한 기능에 대해 기술하였다.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2007.06a
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• pp.9-10
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• 2007

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.3 no.2
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• pp.25-31
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• 2004

Machinability in metal cutting processes depends on cutting input conditions such as cutting velocity, feed rate, depth of cut, types of work material and tool shape factors. In this study, to assess chip breaking characteristics of a turning process, an equivalent oblique cutting system to this has been established. And the equivalent effective rake angle was determined using side rake angle, back rake angle and side cutting edge angle of the tool. A non-dimensional parameter, Chip breaking index(CB), was used to assess Chip breaking characteristics of chip in conjunction with the equivalent effective rake angle. In case of positive rake angles of the equivalent effective rake, the back rake angle has little effect on the chip breaking characteristics however, in case of negative ones, the side rake angle has some effect on Chip breaking characteristics.

• Journal of the Korean Society for Precision Engineering
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• v.19 no.11
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• pp.96-102
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• 2002

This study is on the estimation method of toot temperature for different tool nose radius and cutting conditions in turning. Experimental analysis has been performed in different cutting conditions such as cutting speed, feed rate, and depth of cut for the tool nose radius, 0.4R, 0.8R using SMC workpiece materials. Tool temperature is measured using a thermo-couple which is embedded in the insert tip. Using multiple linear regression method, the tool temperature can be determined as an exponential equation with cutting variables and tool nose diameters for the different tool materials. The equations determined in this study show a good correlation for the cutting conditions and can be used for a tool temperature estimation technique. The result indicates that the tool temperature decreases for increasing the tool nose radius in general. Also, nose radius hardly influences on the tool temperature compared with cutting speed, feed rate and depth of cut. This method will be useful for the estimation of tool life and temperature using limited experimental data for given cutting conditions.

• Journal of the Korean Society for Precision Engineering
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• v.17 no.12
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• pp.68-75
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• 2000

This paper presents the construction of an ultra-precision machining system and machining experiments using the developed system. The system is composed of air bearing system, granite bed, air pad, and linear feeding mechanism. The cutting conditions have great effect on the surface quality in ultra-precision machining. the ultra-precision machining is mainly processed by several ${\mu}{\textrm}{m}$ depth of cut and feed rate. For this, tools with sharper cutting edge and less tool wear are needed. To satisfy these requirement, diamond is generally used as a tool material for ultra-precision machining. In order to evaluate the cutting characteristics of the PCD and MCD tools on the aluminum alloy, the machining experiments performed using the developed system.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.27 no.6
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• pp.1007-1013
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• 2003

As environmental restriction kas continuously become more strict, machining technology has emphasized on development of environment-friendly technology. In cutting technology, it has been well recognized that cutting fluids might have undesirable effects on workers health and working environment. In this study, compressed cold air was used as a replacement for conventional cutting fluids. The cooling effect on cutting tool was analyzed using the finite element method and the computational fluid dynamics. This study focused on the temperature simulation of cutting tool by real flow analysis of cold air. The maximum flow rate and the minimum temperature of compressed cold air are 300ι/min and -30$^{\circ}C$ respectively. To compare the simulation and experimental results, inner temperature of the cutting tool was measured with the thermocouple embedded in the insert. The results show that the analysis of cutting temperature using FEM and CFD is resonable, and the replacement of cutting fluid with cold air is available.

• Journal of the Korean Society for Precision Engineering
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• v.26 no.1
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• pp.138-145
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• 2009

High-efficiency and high-quality machining has become a fact of life for numerous machine shops in recent years. And high-efficiency machining is the most significant tool to enhance productivity. In this study, to achieve high-efficiency machining in turning process, a spindle speed optimization method was proposed based on a cutting power model. The cutting force and power were estimated from the cutting parameters such as specific cutting force, feed, depth of cut, and spindle speed. The time delay due to the acceleration or deceleration of spindle was considered to predict a more accurate machining time. Especially, the good agreement between the predicted and measured cutting forces showed the reliability of the proposed optimization method, and the effectiveness of the proposed optimization method was demonstrated through the simulation results associated with the productivity enhancement in turning process

• Transactions of the Korean Society of Machine Tool Engineers
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• v.14 no.1
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• pp.8-14
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• 2005

The purposes of using cutting fluid during cutting have been cooling, lubricating, chip washing, and anti-corroding. However, the present manufacturing industry restricts the use of cutting fluid because cutting fluid contains poisonous substances which are harmful to the human body. Therefore dry cutting becomes an unavoidable assignment and a lot of researches have studied cutting methods without using cutting fluid. Because dry turning is a continuous work, tools life is reduced by continuous heat generation and surface gets rough due to reduced lubrication, so it is important to consider these situations. In this paper, the way of selecting the optimal machining condition by the minimum number of experiments and the effectiveness of using compressed air in high hardness materials through Taguchi method have been found. Dry cutting using compressed air showed better cutting characteristics than normal dry cutting with respect to by cutting force, tool wear, and surface roughness. Also, the optimal machining condition f3r dry cutting using compressed air could be selected through Taguchi method.